Door lock for trucks, transcontainers and the like

ABSTRACT

Locking device, mainly for doors of trucks, transcontainers and the like. Steel rods extend over outer surfaces of the doors and are pivoted thereto. Each rod has keys, turnably insertable in stationary clasps to provide a lock mechanism. Mating surface portions of the key and clasp are of such construction and form that, regardless of rough service conditions, not only the key finds a safe locking position but the doors can be opened with a minimum of effort.

United States Patent Donath et al.

DOOR LOCK FOR TRUCKS, TRANSCONTAINERS AND THE LIKE lnventors: Hans Donath, Zwickau; Hans-Peter Beier, Wilkau-l-Iasslau; Gottfried Otto, Cainsdorf; Werner Mutz; Winfried Tausch, both of Zwickau, all of Germany Assignee: Ministerium fur Verkehrswesen,

Berlin, Germany Filed: Mar. 1, 1972 Appl. No.: 230,570

US. Cl. 292/218, 292/D1G. 72 Int. Cl. E05c 9/08 Field of Search 292/190, 240, 213, 218,

292/120, DIG. 72

References Cited UNITED STATES PATENTS 12/1964 Chieger etal. 292/218 X 2,767,008 10/1956 Oswald 292/241 3,099,473 7/1963 Pastva, Jr 292/218 X 1,952,112 3/1934 Bartsch 292/218 1,257,051 2/1918 Thomas et al. 292/190 X Primary Examiner-Richard E. Moore Attorney, Agent, or Firm-Albert C. Nolte, Jr.; Edward B. Hunter; C. Bruce Hamburg [57] ABSTRACT Locking device, mainly for doors of trucks, transcontainers and the like. Steel rods extend over outer surfaces of the doors and are pivoted thereto. Each rod has keys, turnably insertable in stationary clasps to provide a lock mechanism. Mating surface portions of the key and clasp are of such construction and form that, regardless of rough service conditions, not only the key finds a safe locking position but the doors can be opened with a minimum of effort.

5 Claims, 8 Drawing Figures PATENTEURPR 2M4 3Q801Q146' sum 2 or 2 DOOR LOCK FOR TRUCKS, TRANSCONTAINERS AND THE LIKE BACKGROUND AND NATURE OF THE INVENTION Locking mechanisms of the indicated type are needed on freight cars, trucks, transcontainers and a variety of other structures. They must provide locking and unlocking operations which are rapid, simple and nevertheless safe, regardless of service conditions which often are extremely rough, as the cars or containers often are exposed to rain, sleet and ice; they can be exposed to serious jarring and bumping; contents may shift and forces may be applied to insides of doors, tending to open them; and on extended service under difficult conditions the doors, door frames and other parts may become distorted to considerable extent.

Of course key and clasp mechanisms are very old and have often been adapted to cars and other structures of the indicated type. In some cases their mating surface portions have been provided with wedgelike ends to insure mutual engagement in the locking operation; however, locks of this type are not always compact enough to allow rapid, safe and effortless operation. Further, the wedge construction often contributes to a moment which tends to open the door instead of keeping it safely locked, particularly when forces act on the doors tending to open them from the inside. Difficulties have also been encountered when dirt or ice could enter the lock.

It has been proposed to provide such locks with outer housings, which could also be used by the provision of special wedge shapes to absorb forces existing between door frame and wing of door. However, other problems were then encountered; for example, too much vertical space within the door frame was required for the lock construction, interfering with the desired utilization of the loading space. In still other constructions the lock mechanism, when being in use, is only able to exert pressure forces to the door frame in vertical direction, that is to say, in direction of the shift rod. The disadvantage of such mechanism, however, is that it may be unable to resiliently return the door frame to its proper shape when the latter being deformed due to distorting forces, for example during loading or unloading conditions when a fork truck drives into the container.

The invention provides an improved lock for service under the indicated conditions and requirements. The improved mode of operation is provided particularly by the following features of the new lock mechanism: The key has a pressure surface which, during a last phase of the unlocking process contacts an outer wall surface of the clasp member; and the key meets outwardly tapering surfaces of the clasp, whereas, in the locked position, the tip of the finger does not touch the surfaces of the window opening in the front wall of the clasp, which it enters, and accordingly will not be loaded by latching forces or reactions. The clasp has curved or tapering surface portions, more fully described hereinafter, which cooperate with the aforementioned key surfaces and support the surface characteristics as outlined here and more fully described in the following part of this disclosure:

IN THE DRAWINGS FIG. 1 is an elevational view of front end and door structure of a container, comprising lock members according to the invention;

FIG. 2 is a similar, but enlarged view, showing details of one of the new locks;

FIG. 3 is a similar view of a detail portion from FIG. 2, shown without other elements which in FIG. 2 partly obscure this portion;

FIG. 4 is a sectional view taken along lines 4-4 in FIG. 3;

FIG. 5 is a plan view of the new look taken along lines 55 in FIG. 3 and showing one position of the lock (Beginning of the locking operation);

FIG. 6 is a generally similar plan view which, however, is taken along lines 6-6 in FIG. 3 and shows another position of the lock (Second phase of the locking operation);

FIG. 7 is a third plan view, taken along lines 77 in FIG. 3 and showing a third position of the lock (Completion of the locking operation); and

FIG. 8 is a fourth plan view taken along the same lines as are followed in FIG. 5 and showing a fourth position of the lock (Final phase of the unlocking operation.)

For general orientation, FIG. 1 shows several pairs of locks according to the invention secured to upper and lower ends of rotatable rods 1 on wings 2 of a front end door of a transcontainer. Each rod 1 is turnably held in two bearings 3 near the upper and lower edges of the door. Directly outside the bearings the rod bears rotatable keys4 which cooperate with clasp 5 on door frame 6. A handle 7 is secured to each rod 1 and extends horizontally therefrom for turning the rod and for thereby closing and opening the lock 4, 5 at each end of the rod. The lock at either end of the rod can be a mirror image of the lock at the other end; also each upper lock of one wing of the door can be a mirror image of an upper lock on the other wing. By means of these arrangements, only two forms of the new lock are needed even for a large transcontainer and the parts can be installed in symmetrical form, as suggested by the drawing, for easy and safe operation.

It will be clear from FIG. 2 that the new lock 4, 5 provided by the invention comprises a pair of mating key and clasp members which have a total of four superposed, horizontally extending lock portions. Upper and lower portions 4a, 4b of the key can embrace an upper portion 5a of the clasp, while a lower part 5b of the clasp is secured to a flange 6a of door frame 6 by a weld seam 6b, which of course is shown only as an example of one way of attachment.

As further shown in FIGS. 3 to 6, upper part 4a of key 4 is a plate member which may have approximately semi-circular form and on the upper surface of which a hub 40 is provided for securement to rod 1 by weld seam 4d. The upper and lower key portions 4a, 4b are interconnected by a curved vertical wall 4e.

Clasp 5 has a vertical wall 50, best shown in FIG. 6, which interconnects for example left end portions of upper and lower clasp walls 5a, 5b. Spaced toward the right from this vertical wall clasp 5 has column 8 extending between its upper and lower walls. Upper wall 5a, as illustrated, overlies only a front portion of lower wall 5b, but has a bulge 9 on its right hand end, extending rearwardly, for engagement with key portions as will now be described.

As best shown in FIG. 5, bulge 9 extends outwardly from the upper end of column 8, both toward the right side and toward the inside, to a curved, doorward facing edge surface 12 of this bulge; however, the right hand end portion of this edge is wedge-shaped and comprises upper and lower inclined surface portions 13a, 13b, as best shown in FIG. 2. Continuing upper and lower surfaces of wall a are horizontal, except at the surfaces of column 8, which are vertical and are limited to a front wall portion 11 of the clasp. These surfaces extend leftward from inclined or wedge portions 13a, 13b

Lower key member 41: has horizontally extending thereform a finger 14 which has a short, wedge-shaped end portion with inclined surfaces 17 (FIGS. 3 and 6) for suitable engagement with wedge-shape clasp end 13b (FIG. 2), while overlying key portion 4a has another tapering surface 16 (FIG. 3). The inclined surfaces 16, 1'7 merge into horizontal surfaces 160, 17a (FIG. 4), so that downwardly facing surface 16, 16a

can act as a thrust surface when the door tends to sag,

while surface 17a will absorb upward reactions of the door. By means of this construction the door can be safely and simply drawn into closed position, by closing lock 4, 5, even if door frame 6 is badly deformed so that large tolerances must be equalized to insure proper sealing of the door on gaskets 2b (FIG. 2).

When the door is closed, the rigid lock members 4d, 5a, 4b, at upper and lower ends of rod 1 insure that the door and door frame are held substantially in their predetermined and proper form. The locking mechanism thus contributes toward rigidity and reinforcement of the entire door structure, as is known to be desirable. The wedge surfaces are limited to edge portions so that they, on completed closure, do not tend to open the door.

A particular improvement is provided as the key 4, at the end opposite the wedge-shaped fingertip 17, has a blunt pressure surface 18 (FIGS. 3 and 8). The use of this surface will be described hereinafter.

Between tapered fingertip 17 and blunt pressure surface 18 the lower and intermediate key portions are recessed, generally to a concave surface 19 of wall 4e (FIG. 6) for engagement with the inner edge 12 of bulge 9 on clasp wall 5a (FIG. 7); however, the key also has an inner, lower rib (FIG. 6) for initial guidance by column 8 during the locking process (FIGS. 5 to 7 OPERATION When the locks are open and the wings of the door are to be locked closed or-center portions of the locks move along broken line 21 (FIG. 7) which iscentered on a door hinge 20 (FIG. 1). However, since deformation of the door frame cannot be avoided entirely, line 21 may intersect clasp 5 in various locations. Typical motions of the key portion are indicated in FIG. 5 at 21a and 21b and it will be assumed that the possible deformation of the door is such that the key portion will not arrive in a location significant to the left of 210.

When the operator then turns handle 7 (FIG. 1) in a counterclockwise direction (curved arrow in FIG. 5), key finger l4 initially engages column 8 and slides along the same, in which process the door may be shifted slightly toward right and, when the fingertip has passed the inner surface of the column, the door begins to be pulled inwardly as the inner edge of rib 15 then slides on the inner surface of column 8 (FIG. 6). In order to avoid any failure of the finger to enter between clasp walls 50, 5b the fingertip as mentioned is wedgeshaped (17) and for example clasp wall 50 also is wedge-shaped (13b, FIG. 2).

During a final phase of this locking operation (FIG. 7) curved pressure face 12 on bulge 9 of the clasp engages inner surface 19 of key wall portion 14 and provides ample engagement surface whereby the key and clasp can absorb such door lock opening forces as may be encountered in the locked condition. This surface engagement is established near and leftwardly beyond travel line 21, whereby a latching effect takes place. Even if substantial door opening forces or reactions be encountered, for example by the shifting of goods within the container, any outwardly directed forces, applied to the door will add to the door locking pressure between the lock members and will not tend to cause separation of these members or springing open of the door.

Vertical reactions between door 2 and frame 6, as channeled into the lock, become effective between surface'portions 16 or 17 on the one hand and bulge 9 on the other hand, depending on the existing deformation of the door. No forces are channeled into the tip of tinger 14, in window 10 of clasp front wall 11, as the key is tapered (17) to avoid such contact. At the same time the key can safely remove dirt or ice which may be accumulated in the lock mechanism as it turns from the position of FIG. 6 into that of FIG. 7.

Unlocking is achieved by turning handle 7 in a clockwise direction, whereupon key 4 slides out of clasp 5. In the last phase of the opening process blunt portion 18 of the key comes in contact with outer wall 11 of clasp 5. As the operator continues to turn the key in the clockwise direction (curved arrow in FIG. 8) a strong force reaction occurs between surface 18 and wall 11 and the door is forced open even if its surfaces are entirely frozen over by a strong coat of ice.

ADVANTAGES OF THE NEW CONSTRUCTION Regardless of distortions between the door and door frame the door is safely pulled into proper position, and is pressed away from the frame with equal safety, in the closing and opening operations, respectively.

The new arrangement of the several parts and surfaces of the key and clasp are such that undesired opening forces are totally avoided even in the event that such forces act on the inside of the door.

As the entire mechanism when closed (FIG. 7), constitutes an almost continuous, solid block of metal, neither dirt, nor snow, nor ice can accumulate in any large amounts, while the container is in transit. Such ice as may form on the door itself is readily overcome by the pressing open operation of FIG. 8.

As only small structures are needed, extending slightly from the hub of the locking rod towards the outside and constituting in substance a semi-circle in which this hub is inscribed '(FIG. 5) and a clasp not substantially larger than the semi-circle (FIG. 7), the resulting compactness of the lock allows production of the two'parts by modern and highly effective methods of production such as precision forging or die casting.

What is claimed is:

1. Locking apparatus for a door comprising a frame to which a door panel is pivoted, said apparatus comprising an operating rod secured to the panel and extending parallel to the axis about which said panel is pivoted and mounted for rotation about its own axis, two key members one secured at each end of the rod and rotatable therewith, and two clasp members one secured to the door frame adjacent each end of the rod for cooperation with the adjacent key member, each clasp member comprising a base, a latching element spaced from the base and a post extending between said base and element; each key member comprising two spaced latch elements interconnected by a web member, said key members being turnable with the rod between locked and unlocked positions, the two latch elements of said key members, in the locked position, being disposed on opposite sides of said latching element of the adjacent clasp member, said latching element of the clasp member comprising wedge surfaces on opposite sides thereof in regions thereof first contacted by said adjacent key member in movement from said unlocked to said locked position, and planar pressure surfaces normal to the axis of said rod in regions positioned for contacting said adjacent key member subsequently to said contact of said wedge surfaces during movement from said unlocked to said locked positions, and said latch elements of said key members having cooperating wedge and pressure surfaces on opposed adjacent surfaces thereof wherein said wedge and pressure surfaces constitute means for vertically aligning said door during movement from said unlocked to said locked position and for supporting said door in said locked position.

2. Apparatus as claimed in claim 1 wherein said web member cooperates with an edge of said latching element of the clasp member during movement of said key member from the unlocked to the locked position, the latching element of the clasp member and the web having matching cooperating pressure surfaces abutting one another, in the locked position of the apparatus, on that side of the rod axis remote from the door panel pivot axis, whereby said cooperating pressure surfaces are constituted as means resisting opening movement of said panel.

3. Apparatus as claimed in claim 1 wherein said key member comprises a surface eccentric to the axis of said rod and cooperating with said post during movement of said key member from the unlocked to the locked position, said eccentric surface and said post constituting means tending to move said door panel in a direction away from the axis about which said panel is pivoted.

4. Apparatus as claimed in claim 2 wherein said key member comprises a surface eccentric to the axis of said rod and cooperating with said post during movement of said key member from the unlocked to the locked position, said eccentric surface and said post constituting means tending to move said door panel in a direction away from the axis about which said panel is pivoted.

5. Apparatus as claimed in claim 1 in which said key member includes a fulcrum surface which, in the unlocked position, bears against an outer surface of said clasp member whereby said fulcrum surface is constituted as a fulcrum during further movement of said key member from the locked position, said further movement tending to force the clasp member and key member apart. 

1. Locking apparatus for a door comprising a frame to which a door panel is pivoted, said apparatus comprising an operating rod secured to the panel and extending parallel to the axis about which said panel is pivoted and mounted for rotation about its own axis, two key members one secured at each end of the rod and rotatable therewith, and two clasp members one secured to the door frame adjacent each end of the rod for cooperation with the adjacent key member, each clasp member comprising a base, a latching element spaced from the base and a post extending between said base and element; each key member comprising two spaced latch elements interconnected by a web member, said key members being turnable with the rod between locked and unlocked positions, the two latch elements of said key members, in the locked position, being disposed on opposite sides of said latching element of the adjacent clasp member, said latching element of the clasp member comprising wedge surfaces on opposite sides thereof in regions thereof first contacted by said adjacent key member in movement from said unlocked to said locked position, and planar pressure surfaces normal to the axis of said rod in regions positioned for contacting said adjacent key member subsequently to said contact of said wedge surfaces during movement from said unlocked to said locked positions, and said latch elements of said key members having cooperating wedge and Pressure surfaces on opposed adjacent surfaces thereof wherein said wedge and pressure surfaces constitute means for vertically aligning said door during movement from said unlocked to said locked position and for supporting said door in said locked position.
 2. Apparatus as claimed in claim 1 wherein said web member cooperates with an edge of said latching element of the clasp member during movement of said key member from the unlocked to the locked position, the latching element of the clasp member and the web having matching cooperating pressure surfaces abutting one another, in the locked position of the apparatus, on that side of the rod axis remote from the door panel pivot axis, whereby said cooperating pressure surfaces are constituted as means resisting opening movement of said panel.
 3. Apparatus as claimed in claim 1 wherein said key member comprises a surface eccentric to the axis of said rod and cooperating with said post during movement of said key member from the unlocked to the locked position, said eccentric surface and said post constituting means tending to move said door panel in a direction away from the axis about which said panel is pivoted.
 4. Apparatus as claimed in claim 2 wherein said key member comprises a surface eccentric to the axis of said rod and cooperating with said post during movement of said key member from the unlocked to the locked position, said eccentric surface and said post constituting means tending to move said door panel in a direction away from the axis about which said panel is pivoted.
 5. Apparatus as claimed in claim 1 in which said key member includes a fulcrum surface which, in the unlocked position, bears against an outer surface of said clasp member whereby said fulcrum surface is constituted as a fulcrum during further movement of said key member from the locked position, said further movement tending to force the clasp member and key member apart. 